METKOHOUHiV WATER. 813 



Cliirk counties. It coiitaiiis tlie iisiuil suiiiinaiics of data rcfiardinf; j^eoKraiiliy, 

 geology, and water resources, with notes on water power, irrigation, agricnllure, 

 eliniat*'. and i>ossil)ilities of cnltnre. 



Preliminary report on the ground waters of San Joaquin Valley, Cali- 

 fornia, W. C. .Mendknhai.l (U. ,S'. Gcoh Surrcjf, Watcr-lf>upplif Paper No. 222, 

 /</». 52, nuip 1). — This paper contains a preliminary account of the geography 

 and general geological conditions of the San Joaquin Valley and of the soils 

 and surface waters, with a nioie detailed report on the nature, extent, distri- 

 tiution, availaltility. and development of underground waters for the whole area 

 and for each county. 



Ground waters and irrigation enterprises in the foothill belt, southern 

 California, W. C. Mendenhai.l (U. H. Gcol. Survey, Water-Supijli/ Paper 21!), 

 pp. ISO. pis. U, p(/s. IG). — This paper reports the results of a continuation of 

 investigations begun in 1903 (E. S. R., 17, p. 70S), covering the region lying 

 along the south base of the San Gabriel Mountains from Cucamonga westward 

 to Los Angeles. This area includes between 55,000 and 60,000 acres of irrigated 

 land, largely in citrus fruits. 



•' lu the same'area there are about 40 flowing wells and nearly 400 pumping 

 plants, representing an investment of at least $1,000,000 in wells and plants 

 alone. There is, of course, an additional heavy investment in the connecting 

 distributing systems. It is estimated that the itumping plants supply the equiva- 

 lent of SO to 100 second-feet of water, continuous flow, used largely for irriga- 

 tion. This outi)ut is not regularly distributed throughout the year, but is 

 largely concentrated in the dry uKinths of July. August, and September, during 

 which, after winters of light nunfall, the production of underground watei's 

 amounts to ','AH\ second-feet or more." 



The pa]ier contains the usual data regarding geography, geological conditions, 

 [ihysiography, rainfall, and underground waters, with brief descriptions of the 

 various irrigation enterprises. 



Water conservation and irrigation (Off. Yearbook Ati.st. 1901-1907, pp. .'/S'l- 

 y.U). — Brief accoinits are given in this article of water-supply works, artesian 

 wells, and irrigation |ilants in Australia. 



The disinfection of drinking water with hydrogen peroxid, II. Reichel 

 (Ztnehr. Ihjtj. ii. I iifektionskrank., 61 (1908), No. J, pp. ^9-70, figs. 2; abs. in 

 ('hem. Zenthl., I9US, J I, No. J8. p. l.i'i'i). — Experiments are rejmrted which in- 

 dicate that ordinary drinking water can be thoroughly disinfected by 0.5 per 

 cent of hydrogen peroxid in 24 hours, by 1.5 per cent in hours, and by a 5 

 per cent scjlution in 3 to 4 hours. The latter is the shortest practicable time 

 in which satisfactory disinfection can bo secured. 



The industrial uses of ozone, particularly for the purification of water, 

 F. .M. Tekkln- ( Trans. Fannlan Nor,, .J {190S), No. 2, pp. Sl-9',, pl.s. 2, figs. 6). — 

 The methods and a|)|tliances used for this purpose are quite fully described. It 

 Is state<l that the use of ozone for the sterilization of water supjilies for drink- 

 ing pur|Mises has the great advantages that it is extremely cheap, very ellicieiit, 

 and absolutely harmless. 



The relative bacteriological contents of can, plate, and natural ice under 

 various conditions, .1. ('. Si-akks (lee and lief rig., 35 (1908), No. 6, pp. 308- 

 •'ilh. — This article calls attention to conditions in a nmnber of plants resulting 

 in s(;riouH contamination of the ice itroduced. 



Water supply and sewerage (1//*/. h'pf. ltd. llraHli Mass.. ,19 {191)7). pp. .^.?- 

 ~')/ I. 'i'lie subjects discu.ss(Ml in this report are as usual advice given to cities, 

 towns, iMiblic institutions, and individuals regarding water and ice sup|>ly ami 

 sewerage, examimition of puldic watt-r supplies and rivers, water-supply statis- 

 tics, and experiments on the i)urilication of sewage and water at the Lawrence 



